NPPES file of Aug 9, 2026

Doctors and health care providers in Fullerton, CA

5,437 individual NPPES records list a practice address in Fullerton, 26th of 812 California cities. The largest group is behavior technician: 2,130, 39% of the city's records, against 18% across California. Page 56 of 109.

CMS NPPES registry, file of Aug 9, 2026 · method · Verify with CMS →

The 8 largest groups in Fullerton

Source: CMS NPPES primary taxonomy, file of Aug 9, 2026.

Fullerton in California

  • Rank in California26th of 812 cities by records
  • Share of the state0.6% of California's records
  • Specialties present25 or more taxonomy codes
  • Top three groups49% of all records

Compared with California as a whole, Fullerton has 14.3× the state's share of pediatric occupational therapist records and 0.37× its share of family medicine physician records.

Providers in Fullerton, alphabetically

  1. Alex Leung, M.DInternal Medicine Physician1669414512
  2. Lawrence Leung, MSWClinical Social Worker1942724695
  3. Alicia Lever, NPAdult Health Nurse Practitioner1346306784
  4. Samuel LevineBehavior Technician1184329211
  5. Kathy Lewczyk, MFTMental Health Counselor1477572766
  6. Delaney LewellynBehavior Technician1528802741
  7. Alia LewisBehavior Technician1538989512
  8. Jerald Lewis, CADC IIAddiction (Substance Use Disorder) Counselor1912366683
  9. Kaitlyn Lewis, PA-CPhysician Assistant1104391713
  10. Marvin LewisBehavior Technician1265194377
  11. Taylor LewisBehavior Technician1548858145
  12. Sharon Lewis-Bultsma, PSY.D.Clinical Psychologist1578031399
  13. Brian Ley, D.D.S.General Practice Dentistry1558552901
  14. Debra LeyelBehavior Technician1003661562
  15. Itzel LeyvaBehavior Technician1871125583
  16. Carol LiMarriage & Family Therapist1306558341
  17. Yang Li, MDInternal Medicine Physician1396035564
  18. Jimmy Liao, M.D.Internal Medicine Physician1104965383
  19. Ebony LibbyBehavior Technician1275181935
  20. Jocelyn Licona RabagoBehavior Technician1891350781
  21. Nhi Lien, FNP-CNurse Practitioner1205535135
  22. Michael Lillie, MDAnesthesiology Physician1740231927
  23. Christopher Lim, MDAnesthesiology Physician1851734362
  24. Louis Lim, MDAnesthesiology Physician1952353831
  25. Shelby LimPhysician Assistant1316602568
  26. Tatiana LimMental Health Counselor1700194735
  27. Sara Limas, CHILD BIRTH EDUCATORRehabilitation Practitioner1568532588
  28. Cynthia Limon, PAPhysician Assistant1558009332
  29. Karen Lin, O.D.Optometrist1093156150
  30. Lori LinPharmacist1356853626
  31. Rachelle Lin, O.D., M.S.Optometrist1487067559
  32. Yuan-Shan Lin, PTPediatric Physical Therapist1871618249
  33. Heather LinaneSchool Psychologist1417814583
  34. Anthony LinaresBehavior Technician1891534608
  35. Isaac LinaresMassage Therapist1225884927
  36. Monica Lind, CCC-SLPSpeech-Language Pathologist1245857903
  37. Kyra Lindner, PAStudent in an Organized Health Care Education/Training Program1316530066
  38. Christopher LindsayBehavior Technician1568215838
  39. Dennis Lindsey, PHDClinical Neuropsychologist1972538114
  40. Janay Lindstrom, PHARMDPharmacist1760181689
  41. Jason Ling, MDEndocrinology, Diabetes & Metabolism Physician1154664597
  42. Sabrina LinharesBehavior Technician1841976545
  43. Megan Linnebur, M.D.Surgery Physician1790042885
  44. Jeremy Lins, MDEmergency Medicine Physician1346828159
  45. Kristin Lipiz, MA, CCC-SLPSpeech-Language Pathologist1730003062
  46. Dorothy Lippman Salovesh, NPFamily Nurse Practitioner1265583033
  47. Manuel LiraBehavior Technician1114740891
  48. Kenneth Paolo Lising, MSN, APRN, FNP-CFamily Nurse Practitioner1003465105
  49. Harvey Liu, D.C.Chiropractor1578736435
  50. Jamie Liu, PA-CPhysician Assistant1801310552

The largest California cities

  1. Los Angeles69,537
  2. San Diego52,937
  3. San Francisco38,143
  4. Sacramento33,083
  5. San Jose20,925

All of California →

How to read this directory

Fullerton, California appears in the CMS National Plan and Provider Enumeration System with 5,437 registered healthcare providers spanning 25 or more distinct NUCC-taxonomy specialties. This count includes every individual clinician who has applied for an NPI and listed a practice address in Fullerton - physicians, dentists, nurse practitioners, physician assistants, chiropractors, physical therapists, optometrists, psychologists, podiatrists, and every other credentialed provider type CMS tracks. It does not measure hospital beds, urgent-care capacity, or whether a given clinic is accepting new patients; it measures the pool of professionals with current NPI enrollment and a Fullerton practice location on file. Every figure is drawn from the federal National Provider Identifier Registry (CMS NPPES) - more than 7 million providers, maintained since May 2007, with 2024 Medicare Part D data, and, according to CMS, can be searched, compared, and traced in our methodology.

The provider mix in Fullerton is weighted toward Behavior Technician (2,130 clinicians, followed by Student in an Organized Health Care Education/Training Program with 269 and Marriage & Family Therapist with 263). That distribution reflects how NPPES records specialty: providers self-select a primary taxonomy code, so a family physician who also practices geriatrics will show up under whichever NUCC code they registered first. Relative to California's population, Fullerton reports roughly 14 providers per 100,000 residents using the state-level denominator, which is a rough proxy rather than a precise access-to-care measurement; the true catchment area of any {cityName} clinician extends beyond the municipal boundary.

For Fullerton patients, this directory is most useful as a starting shortlist. Important: PlainDoctor is a directory of publicly available CMS government data, not a review site, a ranking, or medical advice. NPPES data is self-reported and refreshed monthly; call the practice directly to confirm the provider is still there, accepts your insurance, and is taking new patients.

For informational purposes only; this directory is not medical advice and not a substitute for checking a license. See also: how to find a doctor and how to verify one.

Common questions

How many doctors are in Fullerton, CA?

There are 5,437 registered healthcare providers in Fullerton, CA, covering 25 or more specialties. This includes physicians, dentists, therapists, and other licensed providers.

What are the most common medical specialties in Fullerton?

The most common specialties in Fullerton are Behavior Technician, Student in an Organized Health Care Education/Training Program, Marriage & Family Therapist, Pharmacist, Pediatric Occupational Therapist. Behavior Technician has the most providers with 2,130.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov). Records are self-reported registrations, not licenses.

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.